public static void SquadSetup(out XMVector a, out XMVector b, out XMVector c, XMVector q0, XMVector q1, XMVector q2, XMVector q3) { XMVector ls12 = XMQuaternion.LengthSquare(XMVector.Add(q1, q2)); XMVector ld12 = XMQuaternion.LengthSquare(XMVector.Subtract(q1, q2)); XMVector sq2 = q2.Negate(); XMVector control1 = XMVector.Less(ls12, ld12); sq2 = XMVector.Select(q2, sq2, control1); XMVector ls01 = XMQuaternion.LengthSquare(XMVector.Add(q0, q1)); XMVector ld01 = XMQuaternion.LengthSquare(XMVector.Subtract(q0, q1)); XMVector sq0 = q0.Negate(); XMVector ls23 = XMQuaternion.LengthSquare(XMVector.Add(sq2, q3)); XMVector ld23 = XMQuaternion.LengthSquare(XMVector.Subtract(sq2, q3)); XMVector sq3 = q3.Negate(); XMVector control0 = XMVector.Less(ls01, ld01); XMVector control2 = XMVector.Less(ls23, ld23); sq0 = XMVector.Select(q0, sq0, control0); sq3 = XMVector.Select(q3, sq3, control2); XMVector invQ1 = XMQuaternion.Inverse(q1); XMVector invQ2 = XMQuaternion.Inverse(sq2); XMVector ln_q0 = XMQuaternion.Ln(XMQuaternion.Multiply(invQ1, sq0)); XMVector ln_q2 = XMQuaternion.Ln(XMQuaternion.Multiply(invQ1, sq2)); XMVector ln_q1 = XMQuaternion.Ln(XMQuaternion.Multiply(invQ2, q1)); XMVector ln_q3 = XMQuaternion.Ln(XMQuaternion.Multiply(invQ2, sq3)); XMVector negativeOneQuarter = XMVector.FromSplatConstant(-1, 2); XMVector expQ02 = XMVector.Multiply(XMVector.Add(ln_q0, ln_q2), negativeOneQuarter); XMVector expQ13 = XMVector.Multiply(XMVector.Add(ln_q1, ln_q3), negativeOneQuarter); expQ02 = XMQuaternion.Exp(expQ02); expQ13 = XMQuaternion.Exp(expQ13); a = XMQuaternion.Multiply(q1, expQ02); b = XMQuaternion.Multiply(sq2, expQ13); c = sq2; }